Artificial limb



July 7, 1942. c. w. VAN clsE 2,289,154

ARTIFICIAL LIMEr F'ild Dec. 24, 1941 Stu-www Patented July 7, 1942 UNITED STATES P -l' TENT OFFICE 2 Claims.

This invention relates to an improved artiiicial limb including a foot and leg, and more particularly to an improved ankle joint Afor the articial limb located to provide for the greatest flexibility between the foot and leg portions thereof by locating the joint in the position of the natural yankle joint to thereby produce a lifelike action between the parts of the limb.

Another object of the invention is to provi-de an articial limb wherein the pivotal movement of the ankle joint is resisted by yieldable means which are adjustable for providing the desired amount of action in the joint to suit the wearer.

Another aim of the invention is to provide Figure 1 is a fragmentary vertical sectional` View, `partly in side elevation of the artificial limb,

Figure 2 is a fragmentary transverse vertical sectional view of the same, taken substantially along a plane as indicated by the line 2-2 of Figure l,

Figures 3 and 4 are horizontal sectional views taken through portions of the arti-cial limb and substantially along the planes as indicated by the lines 3-3 'and 4 4, respectively, of Figure 1, and

Figure 5 is a modication of the parts shown in Figure 3.

Referring more particularly to the drawing, wherein like reference characters designate like or corresponding parts throughout the diiferent views, I designates generally the artificial limb in its entirety and including a leg II and a foot I2.

The leg I I includes ian upper, hollow shin portion I3 which is adapted to receive the stump and a lower, substantially solid portion I4 having an upwardly opening, substantially centrally disposed socket I5 which opens into a hollow interior I6 of the shin portion I3, and a similarly disposed downwardly opening socket IT, which opens outwardly of the -lower end of the leg II.

The inner ends of the sockets i5 and I "I fare connected by an opening I8. v

The foot I2 includes an upper portion I9, which portion and the leg H are formed of a suitable rigid material. The foot I2 also includes an integral toe and sole portion 29, formed of a resilient material such as rubber. A plate 2I of resilient metal is .anchored in the toe part of the resilient portion 29 and has one end projecting therefrom and secured to the under side of the foot portion I9 by fastenings 22. The plate 2l forms resilient reinforcing means for the toe of the foot I 2.

The upper foot portion i9 is provided with f an upwardly opening recess or socket 23 containing a socket member 24 which is Ianchored therein. by means of pins 25. The socket member 24 is provided with an annular inwardly bowed upper portion 26 which extends above the upper surface 2'I of the foot portion 'i9 'and which is provided with a restricted opening 23. A pin 29 extends across the socket 24, adjacent its upper end, and is disposed transversely of the foot I2. A graphite bushing Sii is turnably mounted on the pin 29.

The upper surface 21 is curved upwardly toward its forward end and is likewise curved upwardly slightly toward its rear end. The lower end of the leg II forms a surface 3i which is likewise curved upwardly at its forward and rear ends and which is disposed substantially parallel to the surface 21. Between the surfaces 2'I and 3| is mounted a block 32 of resilient material such as rubber, and which is of substantially the same shape as the surfaces 2l and 3l. The block 32 is provided with a central op-ening 33 into which the socket end Z5 extends and into which opens the socket I'I. A bolt 33 is provided with a substantially ball-shaped head 34 which is provided with la slot 35. The slot 35 opens downwardly and laterally and the pin 29 sand the bushing 30 extend therethrough and the ballshaped head 34 is disposed in the upper part of the socket 24. The bolt 33 is provided with a threaded shank 36 which extends upwardly from the head 34 through the openings 28 and 32, through the socket I'I, opening I8 and socket I5 and into the socket I6.

As best seen in Figure 3, the socket I'I is ypolygonal shaped cross section and is provided with a similarly shaped lining 3'I in which is slidably mounted a block 39, which is likewise shaped to conform to the lining 3l to prevent the block from turning therein. rI'he block 33 is provided with a central opening through which the shank 3S extends and is adjustably secured thereto by means of nuts 39 which engage guide block 38, thereabove and therebeneath.

An elongated block 40 of yieldable material, is mounted in the socket I5 and extends into the socket I6 and is provided with a washer 4I at each end thereof. The block 40 and washers 4I are provided with alined openings through which the shank 33 extends. A bolt nut 42 engages the shank 36 and bears against the upper washer 4| and a lock nut 43 engages the shank 36 and bears against the upper side of the nut 42.

From the foregoing, it Will be obvious that the yieldable block 32 is disposed substantially at the level of the human ankle joint so that the joint formedby the socket 24 and the bolt 33 will be disposed in substantially the same location as the human ankle joint. The ball and socket connections formed by these parts permit the bolt 33 to rock forwardly or rearwardly or laterally to the foot l2 and this rocking motion will be resisted by the yieldable block 32 to provide a yielding pivotal movement which can be varied by adjusting the nuts 42 and 43. The guide 38 will prevent any turning movement of the bolt 33 relatively to the socket 34 and will therefore prevent the foot I2 from turning relatively to the leg. The bushing 33 is spaced from the inner end of the slot 35 to allow the bolt to move downwardly when weight is applied to the limb member from above so that the block 32 can cushion the shock which occurs when the weight of the wearer is applied to the articial limb l0, as in walking. Likewise, the block 40 is compressed to permit the leg and foot to yield away from one another. The yieldable toe and sole portion 2! will further act to cushion the shock which occurs in walking. It will thus be apparent that the artificial limb l0, while of very simple construction, can be Worn very comfortably and will have a, very life-like action.

If desired, and as illustrated in Figure 5, the bottom socket of the leg can be made circular in cross section, as indicated Ha, and can be provided with a lining 31a which can be pressed therein to prevent the lining from turning relatively to the socket, and which can be provided with a polygonal shaped bore to receive and slidably mount the guide 38. Various other modications and changesv are contemplated and may obviously be resorted to, provided they fall within the spirit and scope of the invention as hereinafter defined by the appended claims. 4

I claim as my invention:

1. An artificial limb comprising a substantially rigid leg, a foot having an upper part of substantially rigid material, a yieldable member disposed between the leg and said upper part of the foot, means for pivotally connecting the upper part of the foot to the leg, said connecting means combining with the yieldable member to provide a limited resilient, pivotal movement between the foot and leg, said connecting means including an upwardly opening socket member anchored in the upper foot portion and having a restricted upper end, said yieldable member having an opening into which the upper end of the socket member extends, a bolt having a ballshaped head disposed in the upper end of the socket member and provided with a slot which opens outwardly, downwardly and laterally of the limb, a pin extending through the socket member and through the slot in the bolt head, and said bolt having an upwardly extending shank which extends into and is adjustably secured to the leg.

2. An artiiicial limb comprising a substantially rigid leg, a foot having an upper part of substantially rigid material, a yieldable member disposed between the leg and said upper part of the foot, means for pivotally connecting the upper part of the foot to the leg, said connecting means combining with the yieldable member to provide a limited resilient, pivotal movement between the foot and leg, said connecting means including an upwardly opening socket member anchored in the upper foot portion and having a restricted upper end, said yieldable member having an opening into which the upper end of the socket member extends, a bolt having a ballshaped head disposed in the upper end of the socket member and provided with a slot which opens outwardly, downwardly and laterally of the limb, a pin extending through the socket member and through the slot in the bolt head, said bolt having an upwardly extending shank which extends into and is adjustably secured to the leg, a socket embedded in the lower end of the leg, and a guide slidably engaging the socket and held against turning movement relatively thereto, said bolt shank extending through and being clamped to the guide to prevent the bolt from turning relatively to the foot and leg.

CLIFFORD W. VAN OISE. 

